Preparation, characterization, and biodistribution of breviscapine proliposomes in heart

Current Advances in the Use of Nanophytomedicine Therapies for Human Cardiovascular Diseases

Considering the high prevalence of cardiovascular diseases (CVDs), the primary cause of death during the last several decades, it is necessary to develop proper strategies for the prevention and treatment of CVDs. Given the excessive side effects of current therapies, alternative therapeutic approaches like medicinal plants and natural products are preferred. Lower toxicity, chemical diversity, cost-effectiveness, and proven therapeutic potentials make natural products superior compared to other products. Nanoformulation methods improve the solubility, bioavailability, circulation time, surface area-to-volume ratio, systemic adverse side effects, and drug delivery efficiency of these medications. This study intended to review the functionality of the most recent nanoformulated medicinal plants and/or natural products against various cardiovascular conditions such as hypertension, atherosclerosis, thrombosis, and myocardial infarction. Literature review revealed that curcumin, quercetin, and resveratrol were the most applied natural products, respectively. Combination therapy, conjugation, or fabrication of nanoparticles and nanocarriers improved the applications and therapeutic efficacy of herbal- or natural-based nanoformulations. In the context of CVDs prevention and/or treatment, available data suggest that natural-based nanoformulations are considerably efficient, alone or in blend with other herbal/synthetic medicines. However, clinical trials are mandatory to elucidate the safety, cardioprotective effect, and mechanism of actions of nanophytomedicines.

Enhanced local bioavailability of single or compound drugs delivery to the inner ear through application of PLGA nanoparticles via round window administration

In this paper, the potential of poly(D,L-lactide-co-glycolide acid) (PLGA) nanoparticles (NPs) for carrying single or compound drugs traversing the round window membrane (RWM) was examined after the round window (RW) administration of different NPs to guinea pigs. First, coumarin-6 was incorporated into PLGA NPs as a fluorescent probe to investigate its ability to cross the RWM. Then, PLGA NPs with salvianolic acid B (Sal B), tanshinone IIA (TS IIA), and total panax notoginsenoside (PNS) including notoginsenoside R1 (R1), ginsenoside Rg1 (Rg1), and ginsenoside Rb1 (Rb1) were developed to evaluate whether NPs loaded with compound drugs would pass through the RWM and improve the local bioavailability of these agents. PLGA NPs loaded with single or compound drugs were prepared by the emulsification solvent evaporation method, and their particle size distribution, particle morphology, and encapsulation efficiency were characterized. In vitro release study showed sustained-release profiles of Sal B, TS IIA, and PNS from the NPs. The pharmacokinetic results showed that NPs applied to the RWM significantly improved drug distribution within the inner ear. The AUC0-t of coumarin-6 in the perilymph (PL) following RW administration of NPs was 4.7-fold higher than that of coumarin-6 solution, and the Cmax was 10.9-fold higher. Furthermore, the AUC(0-t) of R1, Rg1, and Rb1 were 4.0-, 3.1-, and 7.1-fold greater, respectively, after the application of NPs compared to the compound solution, and the Cmax were, respectively, 14.4-, 10.0-, and 16.7-fold higher. These findings suggest that PLGA NPs with unique properties at the nanoscale dimensions have a powerful ability to transport single or compound drugs into the PL through the RWM and remarkably enhance the local bioavailability of the encapsulated drugs in the inner ear. The use of PLGA NPs as nanoscale delivery vehicles to carry drugs across the RWM may be a promising strategy for the treatment of inner ear diseases.

Improved oral bioavailability of breviscapine via a Pluronic P85-modified liposomal delivery system

Objectives

Breviscapine, a hydrophobic drug used for treating cardiovascular disease, was encapsulated in liposomes to improve its pharmaceutical characteristics. This study describes a novel liposome composition approach to specifically inhibit the P-glycoprotein efflux system.

Methods

Breviscapine-loaded Pluronic P85-coated liposomes were prepared by the thin film hydration technique. The particle size, zeta potential and encapsulation efficiency of the formulations were characterized. In-vitro drug release and permeability of Caco-2 cells were investigated. In-vitro characteristics and pharmacokinetics of the liposomes were evaluated in rat studies.

Key findings

The Pluronic P85-modified liposomes dispersed individually and had an approximate diameter of 118.8 ± 4.9 nm and a zeta potential of −35.4 ± 1.5 mV. Encapsulation efficiency was more than 90%. The use of the P85-coated liposomes resulted in significantly (P < 0.05) increased absorption of breviscapine in Caco-2 cells and in 5.6-fold enhancement in its oral bioavailability in rats.

Conclusion

The P85-modified liposomes for the oral delivery of breviscapine were prepared using l-α-phosphatidylcholine (soy-hydrogenated) and cholesterol with a narrow size distribution. This method seems to effectively enhance the bioavailability of breviscapine in rats.

A new strategy for enhancing the oral bioavailability of drugs with poor water-solubility and low liposolubility based on phospholipid complex and supersaturated SEDDS

A novel supersaturated self-emulsifying drug delivery system (Super-SEDDS) loaded with scutellarin-phospholipid complex (SPC) was developed. The system aimed to address the limitations presented by conventional SEDDS as delivery carriers for drugs with poor water-solubility, low liposolubility and high dose. As an intermediate, SPC was first prepared based on the response surface design. The presence of amorphous scutellarin was demonstrated through differential scanning calorimetry (DSC) and X-ray diffraction (XRD), while enhanced liposolubility was confirmed through comparison with scutellarin powder via an octanol/water distribution test. On the basis of the solubility study and ternary phase diagram, Super-SEDDS containing SPC of up to 200% equilibrium solubility (S_eq) was designed, which composed of ethyl oleate, Cremophor RH40 and Transcutol HP with a ratio of 60∶25∶15 (w/w%). The subsequent in vitro lipolysis study and ex vivo intestinal absorption test indicated that Super-SEDDS enhanced the cumulative dissolution from 70% to 100% and improved the intestinal absorption from 0.04 to 0.12 µg/cm² compared with scutellarin powder. Furthermore, an in vivo study demonstrated that Super-SEDDS achieved the AUC_0-t of scutellarin up to approximate 1.7-fold as scutellarin powder. It was also proved superior to SPC and the conventional SEDDS. Super-SEDDS showed great potential for expanding the usage of SEDDS and could act as an alternative to conventional SEDDS.

Solid dispersion tablets of breviscapine with polyvinylpyrrolidone K30 for improved dissolution and bioavailability to commercial breviscapine tablets in beagle dogs

Breviscapine, one of cardiovascular drugs extracted from a Chinese herb Erigeron breviscapinus, has been frequently used to treat cardiovascular diseases such as hypertension, angina pectoris, coronary heart disease and stroke. However, its poor water solubility and low bioavailability in vivo severely restrict the clinical application. To overcome these drawbacks, breviscapine solid dispersion tablets consisting of breviscapine, polyvinylpyrrolidone K30 (PVP K30), microcrystalline cellulose and crospovidone were appropriately prepared. In vitro dissolution profiles showed that breviscapine released percentage of solid dispersion tablets reached 90 %, whereas it was only 40 % for commercial breviscapine tablets. Comparative pharmacokinetic study between solid dispersion tablets and commercial products was investigated on the normal beagle dogs after oral administration. Results showed that the bioavailability of breviscapine was greatly increased by 3.45-fold for solid dispersion tablets. The greatly improved dissolution rate and bioavailability might be attributed to intermolecular hydrogen bonding reactions between PVP K30 and scutellarin. These findings suggest that our solid dispersion tablets can greatly improve the bioavailability as well as the dissolution rate of breviscapine.

Novel multiple agents loaded PLGA nanoparticles for brain delivery via inner ear administration: in vitro and in vivo evaluation

The aim of this study was to develop novel multiple agents loaded poly (D,L-lactide-co-glycolide acid) (PLGA) nanoparticles (NPs) and evaluate their potential for brain delivery via inner ear administration. PLGA NPs loaded with salvianolic acid B (Sal B), tanshinone IIA (TS IIA) and panax notoginsenoside (PNS) were prepared by double emulsion/solvent evaporation method. It was observed that optimized NPs displayed satisfactory encapsulation efficiency and desired sustained-release characteristics. NPs following intratympanic administration (IT) in guinea pigs greatly improved drug distribution within the inner ear, cerebrospinal fluid (CSF) and brain tissues compared with intravenous administration (IV). Pharmacodynamic studies demonstrated that NPs following IT markedly inhibited oxidizing reactions and protected the brain from cerebral ischemia reperfusion (I/R) injury by upregulating superoxide dismutase (SOD) activity both in serum and brain tissues, simultaneously significantly reducing the levels of malondialdehyde (MDA) and nitric oxide synthase (NOS). Moreover intratympanic delivery did not cause injury of cochlear function by preliminary study on the toxicity. These findings suggested that PLGA NPs-based delivery system via inner ear administration was a promising candidate to brain delivery for the treatment of brain diseases.

Lipid emulsion as a drug delivery system for breviscapine: formulation development and optimization

In this study, we developed an optimized formulation of a breviscapine lipid emulsion (BLE) and evaluated the physicochemical properties and in vivo pharmacokinetics of BLE in rats. For the preparation of the lipid emulsion, soybean oil and oleic acid were used as the oil phase, lecithin and poloxamer 188 as surfactants and glycerol as co-surfactant. An optimized formulation consisting of soybean oil (10.0%), oleic acid (0.9%), lecithin (1.5%), poloxamer 188 (0.4%), and glycerol (2.25%) was selected. The results showed that the average particle size, polydispersity index, and zeta potential of the optimized formulation were 183.5 ± 5.5 nm, 0.098 ± 0.046, and -35.0 ± 2.5 mV, respectively. The BLE was stable for at least three month at room temperature. After a single intravenous dose of 4 mg/kg to rats, the AUC of scutellarin from the lipid emulsion was about 1.5-fold higher than that of the commercial product (breviscapine injection). In conclusion, the optimized formulation of BLE showed positive results over the commercial product in terms of the physicochemical properties and pharmacokinetics of BLE in rats.

Preparation, characterization and evaluation of breviscapine lipid emulsions coated with monooleate-PEG-COOH

Series of monooleate-modified PEG with active carboxylic terminus on the other end (MO-PEG-COOH) were used to modify the lipid emulsions surface to prepare a sterically stabilized lipid emulsions for carrying Traditional Chinese Medicine - breviscapine. Based on the research of relationship between polymer structure and prolonged circulation activity, we developed an optimized formulation and a technological method to prepare the sterile and stable MO-PEG(10,000)-COOH (Bre-LE-PEG(10,000)) coated breviscapine lipid emulsions (Bre-LE) for intravenous administration. Follow the optimum preparation, the average particle size, polydispersity index, zeta potential, Ke value and content of final product were determined to be (207.1±8.5)nm, 0.197±0.005, (-33.6±2.0)mV, (21.1±2.3)% and (95.0±1.8)% respectively (n=3). The characteristics, stability and safety of Bre-LE-PEG(10,000) were also studied with Bre-LE as a control. Increased plasma concentration by surface modification of the lipid emulsions may enhance the pharmacological activity of breviscapine to promote blood circulation.